Apparatus for carbon black manufacture



Sept. 3,1963 H. R. PERRY APPARATUS FOR CARBON BLACK MAUFACTURE FiledJuly 15. 1960.

Hall I? Perry by c 4 United States Patent M Carbon Company, Houston,Tex., a corporation of Delaware Filed July 15, 1960, Ser. No. 43,189

1 Claim. ((11. 23259.5)

This invention relates to the manufacture of carbon black from petroleumoils, or any type hydrocarbon, such as shale oil, coal tar, etc.

It is, of course, well known in the art that superior grade carbonblacks are obtained by rapidly cracking a finely divided hydrocarbon ata relatively high temperature in a turbulent atmosphere wherein the rateof heat transfer to the hydrocarbon is very rapid. Also that, whenpreheated air is used, a higher yield is obtained due to the fact that asmaller portion of the hydrocarbon has to be burned to heat the gasesand remaining hydrocarbon up to the cracking temperature. The velocityof the gas ,is very high (being, in some instances, above the speed ofsound) and the high temperatures which are involved (especially whenproducing carbon black of small particle size) tremendously reduce theperiod of utility of the reactor, when the latter is, for the most part,composed of costly refractory material.

Among the objects of the present invention is the provision of anapparatus for making carbon black which results in materially reducedproduction cost without loss in quality.

Another object is to provide an apparatus for attaining the foregoingobjectives which is comparatively simple and inexpensive to install,operate and maintain.

The invention, then, comprises the features hereinafter fully, describedand as particularly pointed out in the claim, the following descriptionand the annexed drawings setting forth in detail certain illustrativeembodiments of the invention, these being indicative of but several of anumber of ways in which the principles of the invention may be employed.

In said drawings:

FIGURE 1 is a fragmentary longitudinal elevation, partly in section, andillustrating one form of apparatus which embodies the teachings of thepresent invention; and

FIGURES 2 and 3 are transverse sectional views taken on the lines 2-2and 33, respectively, of FIGURE 1.

Referring more particularly to the drawings, the numeral 1 designates anelongate metallic cylindrical housing within which there isconcentrically disposed a cylinder 2 which is composed entirely ofmetal. This metallic cylinder 2 carries on its outer surface a series oflongitudinally extending radial fins 4 which are also composed entirelyof metal, and constitutes what is known in the art as a tin-tube. Suchfin-tubes are frequently formed of stainless steel and are heatresistant to a substantial extent. The fin-tube 2 forms the downstreamend of the combustion chamber or reactor of the apparatus of the presentinvention; and it is shown as provided on its upstream end with anannular flange 5.

It has heretofore been proposed to construct the entire combustionchamber or reactor of metal; but it has been found that considerablesurface oxidation occurs on the exteriors thereof, and the same may meltdue to excessively high temperatures at the combustion end of thereactor, unless, of course, the metal utilized is a special (andnecessarily expensive) high-temperature alloy. The teachings of thepresent invention contemplate a refractory lined or shielded tubedisposed in axial alignment with the upstream end of the fin-tube 2 inorder to protect this high-temperature area or section of the reactorwhere 3,102,7h0 Patented Sept. 3, 1963 initial combustion takes place.As distinguished from the considerably more costly fin-tube, thisupstream tube may be formed of simple steel, as shown at 6, and providedwith a refractory liner 8. The downstream end of the metallic cylinder 6may be provided with an annular flange 7 which is suitably connected tothe annular flange 5 of the (downstream) finatube 2. It will beunderstood, however, that the aforementioned means for connecting thedownstream tin-tube 2 and the upstream metallic cylinder 6 are simplyillustrative and that other, and perhaps more suitable, means may beemployed in lieu thereof. As shown in the drawings, the inside diameterof the refractory cylindrical liner 8 in the metallic cylinder 6 issubstantially the same as that of the (all metal) tin-tube 2. Thisrefractory liner 8 is pre-cast and may be composed of any refractorywhich possesses a sufliciently low thermal co-eiiicient (such as siliconcarbide) in order that it may withstand sudden heat shock withoutcracking. Other suitable materials include the carbides of otherrefractory metals, such as zirconium, titanium, molybdenum, etc.

According to an acceptable embodiment, the refractory pre-cast liner 8may be of between approximately one and approximately three inches inthickness, have an inside diameter of approximately eight inches forcooperation with a fin-tube 2 of corresponding internal dimension; andit may be from approximately four to approximately eight feet in length.

The (all metal) fin-tube 2 maybe of any length which is found suitableand it communicates at its downstream end with a carbon black collectingsystem and an. area provided with one or more quench-water sprays; allof said elements being, of course, well-known in the art.

Referring to the left-hand end of FIGURE 1, the burner is shown ascomprising a tube 10* which extends through a packing gland 12 in thecenter of the adjacent end wall of the housing 1 and extends axiallyinto the cylindrical or drum-like compartment 14 which is formed betweenthe end wall of the housing and the upstream end of the refractorypre-cast cylindrical liner 8. A tube 18 is disposed concentrically inthe tube 10' and extends equidistantly into the cylindrical or drum-likecompartment 14, the ends of said tubes being welded to a verticallydisposed and centrally apertured plate or disk 2% As shown in thedrawings the diameter of the plate or disk 29 is considerably greaterthan the outside diameter of the tube lit: and the diameter of itscentral aperture is substantially that of the inside diameter of thetube 18.

Immediately behind the plate or disk 23, the tube 10 is provided with aseries of evenly spaced apertures 22.

An oil pipe 26 is disposed concentrically within the tube 18 andterminates in a spray head 23, the outer end of which is flush with theouter face of the disk 29. A suitable oil constituting the carbon blackfeedstock is supplied to the oil pipe 26.

Axial air is supplied to the interior of the inner tube 18.

Combustion gas is supplied to the annular space between the inner tube18 and outer tube 10 and emerges through the apertures 22 in the latter.

From the foregoing construction and arrangement it will be observed thatcombustion air enters the air inlet '30, passes along the annular spacebetween the interior of housing 1 and the exterior of the fin-tube 2,then along the exterior of the metallic cylinder 6 and then into thecylindrical or drum-shaped compartment 14 and finally into combustionarea within the refractory liner 9. The combustion area of therefractory cylindrical liner 9 is divided into the three followingzones:

I. Oxidizing zone A which is indicated by radiating this willnecessarily result in an increase in cost.

dash lines. In this zone there is an excess of oxygen above thatnecessary to burn all the gas from the hereinbefore described gasburner.

II. Reducing zone B indicated by radiating solid lines.

This zone includes the volume covered by the oil spray from the sprayhead 28 and when there is an excess of hydrocarbon above that which canbe consumed by the air.

III. Boundary zone C marked by heavy solid lines, which is theoreticallyof a modified bent cone shape, indicating the boundary area which isbetween oxidizing zone A and reducing zone B. In this zone or area thereis just enough oxygen to consume all the oil and gas by combustion andthus temperatures above 3000 F. may be reached; the hottest refractoryarea being where the reducing zone C intersects with the inside of therefractory liner 9.

It will be understood by those skilled in the art that if desired arefractory cylindrical liner 9 could be substitnted for the entirelymetallic fin-tube 2. However, Also that the other gas burners etc. maybe substituted for the one illustrated herein, which, as such forms nopart of the present invention.

It will be understood by those skilled in the art that manymodifications and variations of the invention as above set forth may bemade without departing from the spirit and scope thereof; and thereforeonly such limitations should be imposed as are indicated in the appendedclaim.

I claim:

In an apparatus for making carbon black, an elongate metallic tubularhousing; -a metallic cylinder disposed concentrically within saidelongate metallic tubular housing and forming the downstream end of acombustion chamber; a second metallic cylinder disposed concentricallywithin said elongate metallic tubular housing and secured to, andaxially communicating with, the upstream end of said first-namedmetallic cylinder; the

inner diameter of said second-named metallic cylinder being larger thanthe inner diameter of said first-named metallic cylinder; a refractorycylindrical lining within said second-named metallic cylinder and havingan inner diameter which is substantially the same as the inner diameterof said first-named metallic cylinder thereby providing at this point aperipheral surface for confining the gases flowing downstream which isof substantially uniform diameter; said axially aligned metalliccylinders providing an air jacket between their exterior surfaces andthe inner surface of said elongate metallic tubular housing; one end ofsaid elongatemetallic tubular housing extending beyond the correspondingend of said metallic cylinder and its refractory lining and providing anunobstructed chamber therein; a closure memher for the aforementionedend of said elo-gnate metallic tubular housing; an air inlet disposedadjacent the other end of said elongate metallic tubular housing andcommunicating with the downstream end of said air jacket; a gas burnerdisposed in said unobstructed chamber and in axial alignment with saidupstream end of said secondnamed metallic cylinder; means for supplyingliquid carbon black feedstock to the flame produced by said gas burner;and a series of metallic heat transfer fins on the outer surfaces ofboth of said metallic cylinders; said metallic heat-transfer fins beingadapted to guide the air from said air inlet toward the upstream end ofsaid second-named metallic cylinder.

References Cited in the file of this patent UNITED STATES PATENTS2,498,444 Orr Feb. 21, 1950 2,756,032 Dowel-1 July 24, 1956 2,924,512Webster et al. Feb. 9, 1960 2,967,090 Helmers Jan. 3, 1961 2,976,128Latham et a1. Mar. 21, 1961 3,033,651 Latham et a1. May 8, 1962

